A network storage appliance is a special-purpose computer that provides file service relating to the organization of information on storage devices, such as disks. The network storage appliance or filer includes an operating system that implements a file system to logically organize the information as a hierarchical structure of directories and files on the disks. Each “on-disk” file may be implemented as a set of disk blocks configured to store information, such as text, whereas the directory may be implemented as a specially formatted file in which information about other files and directories are stored. An example of a file system that is configured to operate on a filer is the Write Anywhere File Layout (WAFL™) file system available from Network Appliance, Inc., Santa Clara, Calif.
A filer may be configured to operate according to a client/server model of information delivery to thereby allow many clients to access files stored on a server, e.g., the filer. In this model, the client may comprise an application, such as a file system protocol, executing on a computer that “connects” to the filer over a computer network, such as a point-to-point link or a shared local area network (LAN) or wide area network (WAN). Each client may request the services of the filer by issuing file system protocol messages (in the form of packets) to the filer over the network.
A filer is organized so that it includes one or more of storage “volumes” that comprise a cluster of physical storage disks, defining an overall logical arrangement of storage space. Currently available filer implementations can serve a large number of discrete volumes (for example 150, although this number is subject to increase). Each volume is generally associated with its own file system (WAFL for example). The disks within a volume/file system are typically organized as one or more groups of Redundant Array of Independent (or Inexpensive) Disks (RAID). RAID implementations enhance the reliability/integrity of data storage through the redundant writing of data “stripes” across a given number of physical disks in the RAID group, and the appropriate caching of parity information with respect to the striped data. In the example of a WAFL-based file system, a RAID 4 implementation is advantageously employed. This implementation specifically entails the striping of data across a group of disks, and separate parity caching within a selected disk of the RAID group.
A complex distributed storage arrangement typically requires monitoring and administration of various devices (e.g. disks, filers, etc.) by a competent network administrator at regular intervals. Expected maintenance items and unexpected alert conditions may arise, requiring intervention by the administrator. For example, physical disks may run low on storage or even occasionally malfunction, or other significant events may impair function of a particular volume or of the entire network. In such cases, the administrator should be alerted so that he or she may take appropriate action.
Currently available network administration tools enable an operator to retrieve various status and performance information/reports from individual volumes, or from the entire array of network devices. While such reporting is valuable, it is often limited in usefulness, particularly where a large network of disparate users is present. For example, a large organization such as a bank may have a variety of separate departments, each having its own requirements and characteristics of network use. In order to effectively monitor and administer the various departments it is desirable to divide volumes into separate reporting groups. In addition, it may be desirable to selectively group certain volumes into more than one group where a given volume may cross certain departmental lines. For example upper management may wish to view data from a variety of departments, that are otherwise restricted to individuals in the particular departments. Similarly, certain departments may be subject to system alerts that are particularly critical. For example, the bank's credit card department may be more concerned about low storage than the safe deposit box department due to the relatively greater rate at which credit card transactions are accumulated. Having a low-storage alert tailored to this critical group can expedite action by the administrator.
Accordingly, it is an object of the present invention to provide a system and method for selectively grouping discrete volumes of a network storage arrangement into separate groups that may be a subset of the overall network architecture. This system and method should provide customization and versatility with respect to the type of information that are reported for the various groups and should allow alert information to be tailored to the particular group.